Closure caps for bottles and jars



Sept. 20, 1960 G. v. MUMFORD ErA L CLOSURE CAPS FOR BOTTLES AND JARSFiled Feb. 27, 1958 l N V E N TO R5 620ml IZHU/YFOXD Y KALBHH WHITNEYUnited States Patent I 7 2,953,272 CLOSURE CAPS FOR BOTTLES AND JARSFiled Feb. 27, 19 's, Ser. No. 717,928 I 2 Claims. 01. 21541 The presentinvention relates to improvements in closure caps for bottlesand jarsand hroraparticularly to venting means for. such caps. which will permitmaintenance of safe internal pressures without leakage of the contents.v t 1 An object of our invention is the provision of simple andeifective means incorporated in a substar'ltiallyv allthermoplasticclosure cap for bottles and jars which will permit escape of excess gasto the atmosphere and immediately thereafter efiect proper resealing ofthe container, irrespective of whether the latter stands alone or is atthe bottom of a stack with the weight of the other containers applyingtop pressure to the closure cap.

Another object of our invention is the provision of a closure cap of theabove character in which a relatively heavy semi-rigid ring andattaching flange or skirt element carry a flexible concavo-convexdiaphragm, the latter formed with a sealing surface normally eflectivelycontacting a sealing surface on a bottle or jar, but capable ofseparation from the latter for venting excess gas from the bottle.

A further object of our invention is the provision of a closure capformed of thermoplastic material and incorporating a concavo-convexcentral diaphragm having an annular marginal element normally sealinglyengaging an internal sealing surface on a bottle or jar but momentarilyseparable from the latter under excessive internal gas pressure.

It is also an object of our invention to provide a novel arrangement ofvent grooves and channels which, although permitting ready escape ofexcess gas pressure as explained above, will not under normal conditionsallow communication between the atmosphere and interior of thecontainer.

Other objects will be in part apparent and in part pointed outhereinafter.

In the drawings:

Fig. 1 is a fragmentary sectional view showing a closure capincorporating our invention affixed to a container.

'Fig. 2 is a sectional view on a reduced scale taken substantially alongthe plane of line 2-2 of Fig. 1.

Fig. 3 is a fragmentary detail sectional view showing the ventingposition resulting from upward flexing of the diaphragm under internalpressure.

Fig. 4 is a fragmentary detail sectional view showing in full lines thediaphragm position indicated by dotted lines in Fig. 1.

Fig. 5 is a fragmentary sectional view of a slightly modified form ofour invention.

In the illustrated embodiment of one form of our invention (Figs. 1-4)it is shown in conjunction with a glass jar or bottle provided with areduced neck 11 defining a mouth 12. This neck is formed externally justbelow the rim 13 with an annular abutment 14 facing generally downwardand capable of holding engagement with a portion of a closure cap 0 aswill be apparent presently. An annular internal sealing surface 15 isformed substantially at the juncture of the rim 13 and "ice interiorsurface of the neck 11, the latter surface being tapered downwardly andinwardly if preferred.

The closure cap C which is formed of plastic or other elastomericmaterial comprises a relatively heavy semirigid ring 20 and an annulardepending attaching skirt 21 of lesser diameter than the maximumdiameter of the ring. Thus a continuous ledge 22 is provided for removaland application purposes. This attaching skirt is formed internally nearits lower margin with a projection 23 which takes over and holdinglyengages the aforementioned abutment 14.

A flexible concavo-convex diaphragm or disk 24 has its peripheralportions connected to the inner margin of the aforementioned ring 20. Inthat form of our invention shown in Figs. 1-4, a narrow annular flange25 and an inwardly downwardly directed wall 26 interconnect v thediaphragm and ring. The inclined wall 26 is positioned to normallycontact the sealing surface 15 throughout the length of the latter. Itmay flex upwardly to break such sealing contact when gas pressureinternally of the container becomes excessive. Any such excess gasescapes to the atmosphere and thereupon the seal is reestablished.

Such escape of excess gas is made possible through the provision of anannular channel or groove 27 in the lower side of the closure capsubstantially at the juncture of the inclined wall 26 and flange 25.This places the groove almost immediately over the upper, outer marginof the sealing surface 15.

A multiplicity of radial channels 28 extend along the lower side of saidflange 25 and thence downward along the interior of the attaching skirt21 opening through the lower margin of the latter. Because these ventsare formed as channels in the relatively heavy portions of the closurecap it is apparent that the weight of stacked jars will notdetrimentally affect the venting function of these channels. Thethickness of the ring portion 20 is such that its upper surface lies ina horizontal plane well above that occupied by the diaphragm when thelatter is flexed to its uppermost position. Thus there is nointerference whatsoever to venting when necessary.

If desired, a price carrying disk 29 of any suitable material may besecured in place just above the diaphragm.

In Fig. 5 the closure cap generally is constructed as in the preferredform. However the diaphragm 24 carries a depending sealing flange or lip30 which tapers downwardly and inwardly in the same fashion as thepreviously mentioned wall 26. The flexibility of both said wall 26 andthe lip 30 as well as their position relative to the diaphragm and ringare such that effective sealing contact with the glass is providedirrespective of whether the closure cap is seated upon the container asin Fig. 3 or positioned as in Fig. 1.

It is believed apparent in view of the above that normally the closurecap effectively seals the container and with the building up ofsuflicient internal pressure the diaphragm flexes upwardly and vents theexcess gas to the atmosphere through the annular groove 27 and radialvent channels 28. Normally expected top pressure cannot seal off theradial vent channels 28.

Modifications may be resorted to within the spirit and scope of theappended claims.

We claim:

1. A venting-type closure cap for bottles and jars, said cap formed of aresilient thermoplastic material and comprising a relatively heavysemi-rigid ring, an attaching skirt depending from the ring at a pointnear its inner margin, a resilient generally concave-convex diaphragmpositioned coaxially within the ring, an annular radial flange formedinternally as an integral part of the ring and an annular inclined wallinterconnecting adjacent marginal portions of the radial flange anddiaphragm for sealing contact with the inner surface of a containermouth, said flange and attaching skirt formed internally with at leastone vent-channel extending from the lower margin of the skirt upwardlyand thence radially inward to the upper margin of the inclined wall.

2. In combination a container having an annular wall terminating in acircular mouth defining rim formed at its inner margin with a relativelynarrow annular upwardly inclined sealing surface, said wall alsoprovided with an external downwardly outwardly facing abutment forholding engagement with a closure cap, a venting-type closure cap formedat least in part of a resilient thermoplastic material and comprising arelatively heavy semi-rigid ring of greater diameter than said abutment,a resilient skirt depending from said ring, at a point radially inwardfrom its periphery and telescoped over the abutment, an internal head onthe skirt holdingly engaging the abutment, a resilient generallyconcavo-oonvex diaphragm Within and integral with said ring having itsconvex side facing axially outward and also having a portion immediatelyoverlying the annular rim of the container, an annular inclined sectionconnecting the last named portion and the diaphragm and normally insealing contact with said inclined sealing surface of the container,said diaphragm radially outward of the inclined section and both thering and atpassageways communicate with the interior of the container,the vent passageways including an annular downwazrdly facing channelimmediately above the inner margin of the circular rim and generallyradial grooves arranged about the closure cap and opening at one endinto said a channel and at the other end through the lower margin of theattaching skirt.

References Cited in the file of this patent UNITED STATES PATENTS1,694,851 Glass Dec. 11, 1928 2,325,309 De Swart July 27, 1943 2,693,892Guinet Nov. 9, 1954 2,772,013 Stover Nov. 27, 1956 2,789,719 WheatenlApr. 23, 1957 2,834,496 Boston et a1 May 13, 1958

